An integral of Bessel functions

In summary: Thanks so much for the help!In summary, my teacher gave us a problem as an open question. We attempted to convert it to a problem involving the Wronski Determinant of the Bessel equations, but failed. Luckily, my teacher gave us the solution this morning.
  • #1
S_klogW
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Homework Statement


My teacher gave us a problem as an open question:
To calculate an integral involving Bessel Functions.

Homework Equations


INtegral  copy.jpg

The Attempt at a Solution


I've tried to convert this integral to one in which the Bessel function is in the numerator but failed. Does anyone know how to manipulate this sort of integrals in which the Bessel function is in the denominator?
 
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  • #2
S_klogW said:

Homework Statement


My teacher gave us a problem as an open question:
To calculate an integral involving Bessel Functions.

Homework Equations


View attachment 53473

The Attempt at a Solution


I've tried to convert this integral to one in which the Bessel function is in the numerator but failed. Does anyone know how to manipulate this sort of integrals in which the Bessel function is in the denominator?

I have to admit, at first I didn't expect this integral to even have a closed form solution! So, I cheated an checked wolframalpha to find that it did indeed have one, and then I scoured the wikipedia page on Bessel functions looking for an identity which I thought might help. I found one that did the trick, but I'm not sure how to point you in the direction of it without giving too much away or sending you on a wild goose chase. =S I'm trying to think about how I would have searched for a helpful identity if I didn't already know the answer.

I'm not sure there is a good way to do the search, but here are some suggestions:

-The integrand involves a 1/x factor, so I would probably look at identities which had a 1/x factor somewhere in them.

-Since it's an integral, I would probably also focus on the identities which have a derivative somewhere in them. (As you may be able to massage one of the identities into the form ##d(\mbox{something})/dx = 1/x/J_\nu^2(x)##).

-Sum or integral forms for the bessel functions are not going to be useful because you'd have a (sqaured!) series or integral in the denominator.

Here's the wikipedia page for Bessel functions

Hopefully the suggestions I gave you will help narrow down your search for a useful identity. I'm sorry I can't think of a better way to solve the problem! Also, note that some of the identities hold for more than just ##J_\nu(x)##, so read the text to see if a non- J, Y, H, I or K letter can stand for one or more kinds of Bessel functions!
 
  • #3
Well, in fact this morning my teacher revealed the solution. Just think about the Wronski Determinant of the Bessel equations! This can help us get rid of the 1/x factor!
 

FAQ: An integral of Bessel functions

1. What are Bessel functions?

Bessel functions are a family of special functions that arise in many areas of mathematics and physics. They are named after the mathematician Friedrich Bessel and are often used to solve differential equations that arise in problems involving circular or cylindrical symmetry.

2. What is an integral of Bessel functions?

An integral of Bessel functions is an expression that involves integrating a Bessel function or a combination of Bessel functions with respect to some variable. These integrals often arise in the solution of differential equations, and can be evaluated using various techniques such as contour integration and series expansions.

3. What is the significance of Bessel functions in science?

Bessel functions have many important applications in science, particularly in physics and engineering. They are used in the study of wave phenomena, such as sound and electromagnetic waves, and in the analysis of heat transfer and diffusion processes. They also have applications in signal processing, optics, and quantum mechanics.

4. How are Bessel functions related to other special functions?

Bessel functions are closely related to other special functions, such as the hypergeometric function, the confluent hypergeometric function, and the gamma function. In fact, many of these functions can be expressed in terms of Bessel functions, and vice versa. This allows for the simplification of complicated mathematical expressions and makes Bessel functions a powerful tool in solving problems in various fields.

5. What are some examples of integrals involving Bessel functions?

Some common examples of integrals involving Bessel functions include the Hankel transform, the Fourier-Bessel transform, and the Mellin-Barnes integral. These integrals have applications in the fields of signal processing, image processing, and quantum mechanics, among others. They also have various properties and identities that can be used to simplify or evaluate them in specific cases.

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